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39 Cancri
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Cancer
Right ascension 08h 40m 06.41823s [1]
Declination +20° 00′ 28.0339″ [1]
Apparent magnitude (V) 6.39 [2]
Characteristics
Spectral type G8+ III-IIIb [3]
B−V color index 0.98 [2]
Astrometry
Radial velocity (Rv)33.88 [2] km/s
Proper motion (μ) RA: −35.610 [1]  mas/ yr
Dec.: −11.964 [1]  mas/ yr
Parallax (π)5.3162 ± 0.0589  mas [1]
Distance614 ± 7  ly
(188 ± 2  pc)
Details
Mass2.88 [2]  M
Radius12 [4]  R
Luminosity105 [2]  L
Surface gravity (log g)2.70±0.11 [5]  cgs
Temperature4,954±25 [2]  K
Metallicity [Fe/H]+0.21±0.05 [5]  dex
Age460 [2]  Myr
Other designations
39 Cnc, BD+20°2158, HD 73665, HIP 42516, HR 3427, SAO 80333 [6]
Database references
SIMBAD data

39 Cancri is a star in the constellation Cancer, located about 614  light years from the Sun in the Beehive Cluster ( NGC 2632). It is a challenge to see with the naked eye, having an apparent visual magnitude of 6.39. [2] This object is moving further from the Earth with a heliocentric radial velocity of 34 km/s. [2]

This is an evolved giant star with a stellar classification of G8+ III-IIIb, [3] indicating it has consumed the hydrogen at its core. It is 460 [2] million years old with 2.88 [2] times the mass of the Sun and about 12 [4] times the Sun's radius. The star is radiating 105 [2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,954 K. [2]

References

  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e f g h i j k l m Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal, 150 (3), 88, arXiv: 1507.01466, Bibcode: 2015AJ....150...88L, doi: 10.1088/0004-6256/150/3/88, S2CID  118505114.
  3. ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", The Astrophysical Journal Supplement Series, 71: 245, Bibcode: 1989ApJS...71..245K, doi: 10.1086/191373.
  4. ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (Third ed.): 521–524, arXiv: astro-ph/0012289, Bibcode: 2001A&A...367..521P, doi: 10.1051/0004-6361:20000451, S2CID  425754.
  5. ^ a b Prugniel, Ph.; et al. (July 2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv: 1104.4952, Bibcode: 2011A&A...531A.165P, doi: 10.1051/0004-6361/201116769, S2CID  54940439.
  6. ^ "39 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-03.